bryce@COGSCI.BERKELEY.EDU (05/15/87)
I know a little bit about the Macintosh disk format, but would like to know more. What I think I know follows. Would anyone care add to it? 1> GCR format compatible with the 6 & 2 scheme used by Apple ][ DOS 3.3. 2> Varriable rotational speed. Slower on the outside. Speed value read during (near) horizontal retrace from the sound buffer. A scope pegs the rotation at 350-600 RPM, but factory spec speeds would be of interrest. 3> Since I have never been significantly close to a Mac SE what follows is based on rumor: The SE drive spins at a constant speed and the electronics sort out the difference. This would require a change to the IWM chip. I apologize if I missed the Tech Note. ------------------- "A murderer is one presumed innocent, until proven sane."